Applicant claims, under 35 U.S.C. xc2xa7 119, the benefit of priority of the filing date of May 10, 2000 of a German patent application, copy attached, Ser. Number 100 22 555.1, filed on the aforementioned date, the entire contents of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an angle measuring device for measuring the angular position of a stationary object with respect to an object, which is rotatable around an axis of rotation. The invention furthermore relates to a method for mounting a stator of an angle measuring device, having a rotor rotating around an angle of rotation, on a stationary object.
2. Discussion of Related Art
Angle measuring devices of this type are used for determining the angular position, the angular velocity or other angle-dependent values of a rotatable object and for making them available for purposes of display, control of a machine tool, regulation or other evaluations.
In order to compensate for alignment errors when connecting the rotor of the angular measuring device to the rotatable object, as well as axial and radial deviations of the rotatable object, a coupler is arranged between the stator of the angular measuring device and the stationary object, which connects the stator of the angular measuring device with the stationary object in a manner fixed against relative twisting, but in an axially and/or radially flexible manner.
Angle measuring devices of this type are known, for example, from DE 196 17 585 C1 and DE 195 21 845 C2. DE 196 17 585 C1 corresponds to U.S. Pat. No. 5,808,185, the entire contents of which are incorporated herein by reference.
In connection with the angle measuring device in accordance with DE 196 29 585 A1 it was noted that it is advantageous to arrange the coupler between the stator and the stationary object in the area of the seating of the rotor, i.e. in the vicinity of the place of coupling of the rotor. The work space available in this area is very limited, so that problems regarding the ability to reach the device for radial clamping of the coupler and to actuate it can arise in actual use. Note that DE 196 29 585 C1 corresponds to U.S. Pat. No. 5,758,427, the entire contents of which are incorporated herein by reference.
It is therefore an object of the present invention to disclose an angle measuring device in which the coupler can be clamped without an actuating element having to be accessible from the outside.
This object is attained by an angle measuring device for measuring an angular position of a stationary object with respect to an object which is rotatable around an axis of rotation, that includes a rotor which is connected to the rotatable object which rotates about the axis of rotation and a stator that includes a scanning unit for scanning a graduation, which moves in relation to the scanning unit. A coupler is fastened to the stationary object or stator so as to seat the stator on a stationary object that has a contact face, which extends transversely with respect to the axis of rotation. The coupler has a contact face that extends transversely with respect to the axis of rotation and engages the clamping face of the stationary object or stator so that a clamping force is generated so as to fasten the coupler to the stationary object and wherein the coupler is fixed against relative rotation, but is radially and/or axially elastic.
It is therefore a further object of the present invention to disclose a method for mounting a stator of an angle measuring device on a stationary object, wherein as few as possible mounting steps are required and which can also be performed inside a limited work space.
This object is attained by a method for mounting a stator of an angle measuring device, having a rotor rotating around an axis of rotation, on a stationary object, by attaching a radially and/or axially compensating coupler to the stator of the angle measuring device and axially moving the angle measuring device toward the stationary object, wherein a contact face of the coupler comes into contact with a contact face of the stationary object. Supporting the contact face of the coupler on the contact face of the stationary object, wherein by the axially moving the angle measuring device toward the stationary object the coupler is clamped to the stationary object in a manner fixed against relative rotation.
The advantages which can be achieved by the present invention include in particular the coupler can be installed in the vicinity of the seating of the rotor of the angle measuring device and that, regardless of the restricted installation conditions, the coupler can be fastened on the stationary object in a manner which is solid and fixed against relative rotation. The space of the coupler need not be accessible from the outside for clamping with the stationary object. A solid and space-saving mounting is possible.
Further advantages as well as details of the present invention will become apparent from the ensuing description of an exemplary embodiment in conjunction with the accompanying drawing.